Dielectric properties and optical characteristics of PVA-chitosan blend incorporated by Al₂O₃ and V₂O₅ nanoparticles prepared via lased ablation and their potential for electrical applications

Polyvinyl alcohol (PVA), chitosan (Cs), aluminum oxide (Al₂O₃) nanoparticles, and vanadium pentoxide (V₂O₅) nanoparticles were used to synthesize PVA/Cs-Al₂O₃/V₂O₅ nanocomposites to enhance their structural, thermal, and electrical properties. The Al₂O₃ and V₂O₅ nanoparticles were prepared via laser ablation, and their effects on the properties of the nanocomposite were systematically studied. XRD results confirmed the presence of characteristic peaks of Al₂O₃ and V₂O₅, suggesting strong ion interactions and the formation of ion clusters within the composite. The FTIR spectra indicated significant interactions between the polymer matrix and the nanofillers, as evidenced by the reduced intensity of functional group peaks. FESEM images demonstrated the uniform dispersion of V₂O₅ nanoparticles within the polymer matrix, contributing to enhanced structural properties. UV–vis analysis performed a redshift in absorption edge with increasing V₂O₅ content, indicating modifications in the electronic structure and band gap. The results showed that the optical band gap reduced from 5.24 eV (pristine blend) to 3.43 eV with the highest V₂O₅ content. Additionally, the AC conductivity raised from 1.12 × 10⁻¹² S/cm to 2.62 × 10⁻⁹ S/cm, indicating enhanced charge carrier mobility. Furthermore, the thermal stability improved, as the degradation temperature at 50% weight loss increased from 276 to 368 °C with the incorporation of nanofillers, demonstrating enhanced thermal resistance. These findings highlight the potential of PVA/Cs-Al₂O₃/V₂O₅ nanocomposites for applications in flexible electronics and energy storage devices.